Bioactive glass compositions and dentin hypersensitivity remediation

ABSTRACT

A dental formulation including: a bioactive glass composition as defined herein, in an effective amount; and a suitable carrier as defined herein, in an effective amount. Also disclosed is a method of making and using the dental formulation to treat, for example, dentin sensitivities.

This application is a Continuation of U.S. application Ser. No.16/203,002, filed on Nov. 28, 2018, which claims the benefit of priorityunder 35 U.S.C. § 119 of U.S. Provisional Patent Application No.62/591,423 filed Nov. 28, 2017, the content of which is incorporatedherein by reference in its entirety.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is related commonly owned and assigned USSNProvisional application Nos., filed May 25, 2016:

62/342,384, entitled “BIOACTIVE ALUMINOBORATE GLASSES”;

62/342,377, entitled “MAGNETIZABLE GLASS CERAMIC COMPOSITION AND METHODSTHEREOF”;

62/342,381, entitled “LITHIUM DISILICATE GLASS-CERAMIC COMPOSITIONS ANDMETHODS THEREOF”;

62/342,391, entitled “BIODEGRADABLE MICROBEADS”; and

62/342,411, entitled “BIOACTIVE GLASS MICROSPHERES”; but does not claimpriority thereto.

The present application is also related to commonly owned and assignedUSSN Application No. 62/189,880, filed Jul. 7, 2015, entitled“ANTIMICROBIAL PHASE-SEPARATING GLASS AND GLASS CERAMIC ARTICLES ANDLAMINATES,” which mentions a copper containing laminate having adegradable phase, which phase liberates cooper ion, and a non-degradablephase, but does not claim priority thereto.

The present application is also related commonly owned and assigned USSNapplication Nos.:

62/591,446, filed Nov. 28, 2017, entitled “HIGH LIQUIDUS VISCOSITYBIOACTIVE GLASS”; and

62/591,438, filed Nov. 28, 2017, entitled “CHEMICALLY STRENGTHENEDBIOACTIVE GLASS-CERAMICS”;

62/591,429, filed Nov. 28, 2017, entitled “BIOACTIVE BORATE GLASS ANDMETHODS THEREOF”, filed concurrently herewith, but does not claimpriority thereto.

The entire disclosure of each publication or patent document mentionedherein is incorporated by reference.

BACKGROUND

The disclosure relates to a glass composition, a bioactive glasscomposition, and to methods of making and using the compositions.

SUMMARY

In embodiments, the disclosure provides a glass composition, a bioactiveglass composition, a bioactive dental formulation (e.g., toothpaste),and to methods of making and using the compositions.

In embodiments, the disclosure provides a composition and method fortreating dentin hypersensitivity.

In embodiments, the disclosure provides a group of borate andborosilicate bioactive glasses, an oral care product, for example, atoothpaste, a mouthwash, and like formulations, for the treatment ofdentin hypersensitivity.

In embodiments, the disclosure provides a glass composition that has asignificantly higher rate of occluding of exposed dentin tubules than a45S5-containing toothpaste, demonstrating excellent properties fortreating dentin hypersensitivity.

In embodiments, the present disclosure provides: a bioactive glasscomposition as defined herein, including or excluding selected sourceadditives.

BRIEF DESCRIPTION OF THE DRAWINGS

In embodiments of the disclosure:

FIG. 1 shows a hypothetical scheme of chemical and physical action ofthe disclosed bioactive composition.

FIGS. 2A to 2F show SEM micrographs of test dentin discs after 1 weektreatment with various formulations.

FIGS. 3A to 3C show SEM-EDS analysis of dentin deposition after a 1 weektreatment with an Example 1 containing toothpaste formulation.

DETAILED DESCRIPTION

Various embodiments of the disclosure will be described in detail withreference to drawings, if any. Reference to various embodiments does notlimit the scope of the invention, which is limited only by the scope ofthe claims attached hereto. Additionally, any examples set forth in thisspecification are not limiting and merely set forth some of the manypossible embodiments of the claimed invention.

In embodiments, the disclosed compositions, articles, and methods ofmaking and using provide one or more advantageous features or aspects,including for example as discussed below. Features or aspects recited inany of the claims are generally applicable to all facets of theinvention. Any recited single or multiple feature or aspect in any oneclaim can be combined or permuted with any other recited feature oraspect in any other claim or claims.

Definitions

“Dentin hypersensitivity,” (DH) “dentin sensitivity,” (DS) or like termsrefer to a short, sharp pain caused by cold and heat, air, touch, orchemical or osmotic stimuli, e.g., sweets.

“Occlude,” “occluding,” “occlusion,” or like terms refer, for example,to close up or block off, to obstruct.

“Glass,” “glasses,” or like terms can refer to a glass or aglass-ceramic.

“Glass article,” or like terms can refer to any object made wholly orpartly of glass or a glass-ceramic.

“Flavorant,” “flavor” or like terms can refer to any natural orsynthetic substance that provides organoleptic properties to thedisclosed composition when a user has contact with the composition. Theflavorant can be, for example, a single compound or a mixture ofcompounds. The flavorant can be selected to give the composition orproduct a unique flavor or to maintain flavor consistency betweendifferent product batches or after recipe changes. The flavorant can beany known or discovered compound, for example, diacetyl,acetylpropionyl, acetoin, isoamyl acetate, benzaldehyde, cinnamaldehyde,ethyl propionate, methyl anthranilate, limonene, ethyl decadienoate,allyl hexanoate, ethyl maltol, ethyl vanillin, methyl salicylate, andlike compounds, or mixtures thereof.

Other typical composition components or formulation ingredients areknown to one of skill in the art such as an abrasive, a humectant, acolorant, an antibacterial agent, a surfactant, a whitening agent, abinder, and like components or ingredients, see for example,en.wikipedia.org/wiki/Toothpaste.

“Angiogenesis ability,” “angiogenic,” “angiogenesis,” or like terms,refer to the physiological process by which new blood vessels form frompre-existing vessels.

“Include,” “includes,” or like terms means encompassing but not limitedto, that is, inclusive and not exclusive.

“About” modifying, for example, the quantity of an ingredient in acomposition, concentrations, volumes, process temperature, process time,yields, flow rates, pressures, viscosities, and like values, and rangesthereof, or a dimension of a component, and like values, and rangesthereof, employed in describing the embodiments of the disclosure,refers to variation in the numerical quantity that can occur, forexample: through typical measuring and handling procedures used forpreparing materials, compositions, composites, concentrates, componentparts, articles of manufacture, or use formulations; through inadvertenterror in these procedures; through differences in the manufacture,source, or purity of starting materials or ingredients used to carry outthe methods; and like considerations. The term “about” also encompassesamounts that differ due to aging of a composition or formulation with aparticular initial concentration or mixture, and amounts that differ dueto mixing or processing a composition or formulation with a particularinitial concentration or mixture.

“Optional” or “optionally” means that the subsequently described eventor circumstance can or cannot occur, and that the description includesinstances where the event or circumstance occurs and instances where itdoes not.

The indefinite article “a” or “an” and its corresponding definitearticle “the” as used herein means at least one, or one or more, unlessspecified otherwise.

Abbreviations, which are well known to one of ordinary skill in the art,may be used (e.g., “h” or “hrs” for hour or hours, “g” or “gm” forgram(s), “mL” for milliliters, and “rt” for room temperature, “nm” fornanometers, and like abbreviations).

Specific and preferred values disclosed for components, ingredients,additives, dimensions, conditions, times, and like aspects, and rangesthereof, are for illustration only; they do not exclude other definedvalues or other values within defined ranges. The composition andmethods of the disclosure can include any value or any combination ofthe values, specific values, more specific values, and preferred valuesdescribed herein, including explicit or implicit intermediate values andranges.

Dentin hypersensitivity is a global oral health issue and its treatmentremains a significant challenge for most dental professionals. Dentinhypersensitivity is caused by the absence of the smear layer of dentintubules, which exposes dentinal tubules to thermal, chemical,mechanical, or osmotic stimuli. The movement of the fluid within thetubules stimulates mechanical receptors that are sensitive to fluidpressure, resulting in the transmission of the stimuli to the pulpalnerves and ultimately the pain response. Dentin hypersensitivity cangenerally be treated, for example, by chemical desensitization of thetooth nerve endings, tubule occluding agents or barriers to reducedentin permeability, or both (see S. B. Low, “Reduction in dentalhypersensitivity with nano-hydroxyapatite, potassium nitrate, sodiummonoflurophosphate and antioxidants,” Open Dent J, 2015; (9): 92-97; S.Miglani, “Dentin hypersensitivity: Recent trends in management,” JConsery Dent. 2010, 13(4): 218-224; A. R. Davari, “Dentinhypersensitivity: Etiology, diagnosis and treatment; a literaturereview,” J Dent (Shiraz), 2013, 14(3): 136-145). The use of potassiumnitrate (KNO₃) as a chemical desensitization agent can eliminate thepotassium ion concentration gradient across the nerve cell membrane.Therefore, the nerve cells will not depolarize and will not respond tostimuli (see S. B. Low, supra.). Current tubule occluding agents includefluorides (i.e., formation of calcium fluoride crystals), oxalates(i.e., formation of calcium oxalate), and strontium chloride (i.e., hasaffinity for dentine due to the high permeability and possibility forabsorption into or onto the organic connective tissues and theodontoblast processes) (see S. Miglani, supra.). Additionally,Pro-Argin-based toothpastes can form a dentin-like mineral depositionlayer due to the binding of arginine and calcium carbonate to thenegatively charged dentine surface (see R Kulal, “An in-vitro comparisonof nano hydroxyapatite, Novamin and Proargin desensitizing toothpastes—aSEM study” J Clin Diagn Res, 2016, 10(10): ZC51-ZC54). Recently,silicate glass based toothpastes such as Novamin® and BioMin® (havingfor example less than 40% mol SiO₂, greater than 8% mol P₂O₅), werefound to react with saliva and release calcium, phosphate, or in thepresence of fluoride ions to form hydroxycarbonated apatite orfluorapatite, respectively, over the exposed dentin and within dentintubules (see S. Miglani, supra.; L. J. Litkowski, “Compositionscontaining bioactive glass and their use in treating toothhypersensitivity,” U.S. Pat. No. 6,338,751; and R. Hill, “Bioactiveglass composition,” U.S. Pat. No. 9,168,272)(see also H. E. Strassler,et al., “Dentinal Hypersensitivity: Etiology, Diagnosis and Management”Contin. Ed. Pub.; and M. Han, et al., “In vivo remineralization ofdentin using an agarose hydrogel biomimetic mineralization system,” 7Feb. 2017, in nature.com/srep/).

Dentin treatment using bioactive glass-containing toothpastes isbelieved to be the only treatment method that can provide long periodprotection. Unlike other occluding reagents of dentin tubules, abioactive glass can reliably relieve the pain of dental hypersensitivityfor extended periods permanently. Recently developed aluminoborateglasses have been demonstrated to have excellent biocompatability,enhanced angiogenesis, and can promote wound healing, see for example,the abovementioned commonly owned and assigned copending patentapplications: 62/342,411 and 62/342,384.

In embodiments, the present disclosure provides an array of borate andborosilicate glass compositions that have superior properties and acapacity to treat dentin hypersensitivity compared to known bioactiveglasses.

In embodiments, the present disclosure provides a dental formulation,for example, for oral topical applications, comprising:

a bioactive glass composition in an effective amount, e.g., from 0.1 to10 wt %, comprising a source of:

2 to 70% B2O₃,

1 to 60% SiO₂,

2 to 16% Al₂O₃,

5 to 30% CaO,

1 to 6% P₂O₅,

1 to 20% Na₂O,

1 to 20% K₂O, and

1 to 20% MgO, based on a 100 mol % total of the composition; and

a suitable carrier, in an effective amount of from 99.9 to 90 wt % basedon a 100 wt % total of the composition. The mol % of the source has theequivalent weight percentages of 1 to 60% B2O₃, 1 to 60% SiO₂, 2 to 20%Al₂O₃, 5 to 25% CaO, 1 to 10% P₂O₅, 1 to 20% Na₂O, 1 to 25% K₂O, and 1to 15% MgO, based on a 100 wt % total of the composition.

In embodiments, the disclosure provides a bioactive glass comprising asource of from 5 to 50 mol % SiO₂ (4 to 40 wt %), and the suitablecarrier comprises a source of from 5 to 25 mol % SiO₂ (4 to 20 wt %)(e.g., as an abrasive), based on a 100 mol % (100 wt %) total of thecomposition.

In embodiments, the disclosure provides a dental formulation compositionfurther comprising a source of fluoride ion in an amount of from 1 to 25mol % (1 to 30 wt %) (see, e.g., U.S. Pat. No. 9,168,272).

In embodiments, the disclosure provides a dental formulation compositionwherein the source of fluoride ion is selected, for example, from NaF,SnF₂, CaF₂, and like sources, or a mixture of selected sources.

In embodiments, the disclosed bioactive glass composition and dentalformulation composition containing the disclosed bioactive glasscomposition can be substantially free-of or entirely free-of a source offluoride ion.

In embodiments, the disclosed bioactive composition and dentalformulation composition containing the disclosed bioactive glasscomposition can be substantially free-of or entirely free-of a source oftitanium oxide.

In embodiments, the disclosure provides a dental formulation compositionwherein the bioactive glass composition in an effective amount is from 1to 20 wt % (e.g., from 1 to 10 wt %) and the suitable carrier in aneffective amount is from 80 to 99 wt % (e.g., from 90 to 99 wt %).

In embodiments, the disclosure provides a preferred dental formulationcomposition wherein the bioactive glass composition comprises:

40 to 60% B2O₃,

0.1 to 5% SiO₂,

6 to 10% Al₂O₃,

15 to 25% CaO,

1.5 to 2.0% P₂O₅,

4 to 8% Na₂O,

6 to 10% K₂O, and

6 to 10% MgO, based on a 100 mol % total of the composition. The mol %of the source has the equivalent weight percentages of 30 to 50% B2O₃,0.1 to 5% SiO₂, 8 to 15% Al₂O₃, 15 to 25% CaO, 1.5 to 5% P₂O₅, 4 to 8%Na₂O, 6 to 15% K₂O, and 3 to 8% MgO, based on a 100 wt % total of thecomposition.

In embodiments, the disclosure provides a dental formulation compositionwherein the suitable carrier comprises one or more ingredients selectedfrom: an abrasive, a humectant, i.e., an anti-drying agent such asglycerol, sorbitol, xylitol, 1,2-propylene glycol, polyethyleneglycol,and like compounds, a flavorant, a colorant, an antibacterial agent, asurfactant, a whitening agent, and other like suitable ingredients knownin the art, or a mixture thereof.

In embodiments, the disclosure provides a dental formulation compositionwherein the suitable carrier comprises one or more forms selected from:a gum, a paste, a powder, a toothpaste, a mouthwash, a poultice, a tea,a sucker, a spray, and like forms, or a mixture thereof.

In embodiments, the disclosure provides a remineralizing compositioncomprising: any one of the abovementioned bioactive glass compositionsor combinations thereof, and optionally a suitable carrier such asnon-aqueous carrier for the remineralizing composition.

In embodiments, the disclosure provides a remineralizing compositioncomprising: the abovementioned bioactive glass composition and anoptional suitable carrier.

In embodiments, the disclosure provides a method of treating dentinhypersensitivity or sensitivity comprising:

contacting a dental surface and any of the abovementioned dentalformulations comprising the remineralizing composition.

In embodiments, the contacting the dental formulation has a higherrelative rate of from 50 to 95% of occluding exposed dentin tubulescompared to a dental formulation base formula that is free-of thebioactive glass, i.e., without the bioactive glass present.

In embodiments, contacting the dental formulation can be selected fromat least one of: polishing with a paste formula, rinsing with a liquidformula, injecting with a liquid formula, filling a tooth with acomposite, e.g., typically made of powdered bioactive glass and acrylicresin, or a combination thereof.

In embodiments, the dental surface can have at least one of, forexample: a dentin surface, a dentin tubule, or a combination thereof.

In embodiments, the disclosure provides a dental formulation comprising:

a bioactive glass composition in an effective amount comprising a sourceof:

2 to 70% B2O₃,

2 to 16% Al₂O₃,

5 to 30% CaO,

1 to 6% P₂O₅,

1 to 20% Na₂O, and

1 to 20% MgO, based on a 100 mol % total of the composition; and asuitable carrier, in an effective amount based on the combined 100weight % of the bioactive glass and the carrier. The mol % of the sourcehas the equivalent weight percentages of 1 to 60% B₂O₃, 1 to 60% SiO₂, 2to 20% Al₂O₃, 5 to 25% CaO, 1 to 10% P₂O₅, 1 to 20% Na₂O, 1 to 25% K₂O,and 1 to 15% MgO, based on a 100 wt % total of the composition.

In embodiments, the dental formulation is free of silica such as asource of SiO₂, and free of inorganic potassium salts such as a sourceof K₂O.

In embodiments, the present disclosure is advantaged in several aspects,including for example: the disclosed borate and borosilicate glasscompositions can have a significantly higher rate of occluding of theexposed dentin tubules compared to a 45S5-containing toothpaste, whichresult(s) demonstrate excellent potential of the disclosed bioactiveglass for treating dentin hypersensitivity or dentin sensitivity; thedisclosed bioactive glass compositions can be free-of inorganicpotassium salts, and the disclosed bioactive glass compositions, anddentin treatment formulations, can be silicate free. Novamin® andBiomin® are silicate-containing bioactive glasses.

In embodiments, the disclosure provides borate and borosilicatebioactive glass compositions, for example, as listed in Table 1, thatcan react with mammalian saliva and can release calcium and phosphate toform hydroxycarbonated apatite, or if fluoride ions are present to formfluorapatite (see FIG. 2 and FIG. 3), exhibiting tubule occlusion at thesurface by the formation of a smear layer and within dentin tubules, andrebuild, strengthen, and protect tooth structure. There is alsodeposition of a trace amount of magnesium in the apatite layer (FIG. 3).Normal enamel and dentin contain, for example, 0.44 and 1.23 wt % ofmagnesium, respectively. Magnesium is a co-factor for many enzymes, andstabilizes the structures of DNA and RNA. Magnesium may have stimulatoryeffects on the tooth development and maintenance.

TABLE 1 Bioactive glass compositions in mol percent. Glass Example SiO₂B₂O₃ Al₂O₃ CaO P₂O₅ Na₂O K₂O MgO 1 0 54.6 8 22.1 1.7 6 7.9 7.7 2 9 45 822.1 1.7 6 7.9 7.7 3 18 36 8 22.1 1.7 6 7.9 7.7 4 27 27 8 22.1 1.7 6 7.97.7 5 36 18 8 22.1 1.7 6 7.9 7.7 6 45 9 8 22.1 1.7 6 7.9 7.7 Comparative46.1 0 0 26.9 2.6 24.3 7.9 7.7 Ex 7 (45S5 - control)

Fluoride can be incorporated into the glass compositions in a precursorform of, for example, sodium fluoride (NaF), stannous fluoride (SnF₂),calcium fluoride (CaF₂), and like fluorides or mixtures thereof. Thefluoride incorporated glasses can release fluoride and form fluorapatitein an oral fluid. Fluorapatite is more resistant to acid dissolutionthan hydroxycarbonated apatite.

The fluoride incorporated glasses can also be added into non-aqueousdentifrice matrix, for example, in combination with another bioactiveglass. Fluoride ions are known to aid apatite formation and canstimulate osteoblast division.

In addition to their re-mineralizing toothpaste effect, the disclosedglass compositions and formulations can also be antimicrobial, whichproperty permits, for example, prevention of dental caries, reduceplaque formation, control gingivitis, suppress breath malodor, and likebeneficial effects. The disclosed glass compositions and formulationscan also be incorporated in other professionally applied dentalproducts, such as cleaning and polishing pastes, varnishes,re-mineralizing filling materials, and like formulations.

In embodiments, the disclosure provides a remineralizing compositioncomprising, for example:

a bioactive glass composition in an effective amount, e.g., from 0.1 to10 wt %, comprising a source of:

2 to 70% B₂O₃,

1 to 60% SiO₂,

2 to 16% Al₂O₃,

5 to 30% CaO,

1 to 6% P₂O₅,

1 to 20% Na₂O,

1 to 20% K₂O, and

1 to 20% MgO, based on a 100 mol % total of the composition, andoptionally further comprising a suitable carrier in from 80 to 99.9 wt %to the bioactive glass in from 0.1 to 20 wt % based on the total weightof the composition and carrier. The mol % of the source has theequivalent weight percentages of 1 to 60% B₂O₃, 1 to 60% SiO₂, 2 to 20%Al₂O₃, 5 to 25% CaO, 1 to 10% P₂O₅, 1 to 20% Na₂O, 1 to 25% K₂O, and 1to 15% MgO, based on a 100 wt % total of the composition.

Referring to the Figures, FIG. 1 shows a hypothetical scheme of chemicaland physical action of the disclosed bioactive composition. Themechanism of action, although not limited by theory, is believed toinclude, for example: the bioactive glass particles react with saliva orwater to exchange ions, e.g., Na⁺, K⁺, and like ions, with H⁺, and raisethe pH (100); calcium and phosphate precipitate as calcium-phosphate(110); and calcium-phosphate, or fluoride if present, crystallize toform hydroxycarbonated apatite or fluorapatite on the dentin surface orwithin the dentin tubules (120).

FIGS. 2A to 2F show SEM micrographs of test dentin discs after 1 weektreatment: with a base toothpaste formulation (2A, 2B); a45S5-containing toothpaste (2C, 2D); or an Example 1 containingtoothpaste (2E, 2F), and immersion in artificial saliva. There was nooccluding of dentin tubules for the base toothpaste treatment. Aftertreatment with the 45S5 containing toothpaste, dentin tubules werepartially occluded by crystal-like deposits. After treatment with theExample 1 containing toothpaste, most dentin tubules and dentin surfacewere occluded by crystal-like deposits.

FIGS. 3A to 3C show SEM-EDS analysis of dentin deposition after a 1 weektreatment with the Example 1 containing toothpaste. FIG. 3A shows theSEM having two points selected (black circles added) for furtheranalysis. SEM-EDS analysis showed the apatite formed on and within thedentin tubules were calcium and phosphate precipitate and small trace ofmagnesium (see FIGS. 3B (point 003) and 3C (point 004)).

Materials and Methods

Each glass composition of Table 1 was separately melted and ground to 1to 10 microns using, for example, an air jet mill.

Each ground glass composition of Table 1 was separately formulated intoa dental formulation such as listed in Table 2.

Each dental formulation was evaluated for the ability to occlude dentinediscs made of human molars as detailed in Example 9, i.e., the discshaving dentin tubules were exposed to the dental formulation andcompared to a dental formulation base (control) that was free-of thedisclosed bioactive glass.

TABLE 2 Base and an exemplary BG* containing toothpaste composition.Base Toothpaste Ingredients (control) (base + BG*) glycerol 69.02 64.02sodium lauryl sulphate 1.1 1.1 PEG400 20 20 silicon dioxide 8 8*bioactive glass (BG) — 5 carbopol 940 0.5 0.5 sodium saccharin 0.350.35 flavor 1.03 1.03 Total (wt %) 100 100

Raw materials, equipment, or both, used to produce the compositions ofthe present disclosure, can introduce certain impurities or componentsthat are not intentionally added, and can be present in the final glasscomposition. Such materials can be present in the disclosed compositionsin minor amounts and are referred to as “tramp materials.”

Disclosed compositions can comprise the tramp materials, typically intrace amounts. Similarly, “iron-free,” “sodium-free,” “lithium-free,”“zirconium-free,” “alkali earth metal-free,” “heavy metal-free,” or likedescriptions, mean that the tramp material was not purposefully added tothe composition, but the composition may still comprise iron, sodium,lithium, zirconium, alkali earth metals, or heavy metals, etc., but inapproximately tramp or trace amounts.

Unless otherwise specified, the concentrations of all constituentsrecited herein are expressed in terms of weight percent (wt %).

EXAMPLES

The following Examples demonstrate making, use, and analysis of thedisclosed compositions, formulations, and methods in accordance with theabove general procedures.

Example 1

Glass 1

The composition of Example 1 in Table 1 was prepared as follows: Thesource batch materials in the indicated amounts, including silicondioxide, boric acid, alumina, sodium oxide, potassium oxide, limestone,magnesium oxide, and calcium phosphate, were individually combined. Thebatch source materials were vigorously mixed in a plastic jar using aTurbular mixer. Then they were transferred to a platinum crucible withan internal volume of approximately 650 cc. The crucible was then loadedinto an annealing furnace to calcine the batch at 250° C. for 24 hr. Thecalcined batches were then melted at 1100 to 1300° C. for 6 hr and thenthe glass melt was poured on a steel plate, and annealed at 400 to 500°C.

Examples 2 to 6

Glasses 2 through 6 were likewise prepared as in Example 1 with theexception that the composition or amount used in the batch was differentand as listed in Table 1.

Comparative Example 7

Comparative Glass 7

The composition of Comparative Example 7 in Table 1 was prepared as inExample 1 with the exception that: there is no boric acid or aluminabatched in the comparative glass, see for example US 20140186274, whichmentions a non-aqueous base composition in combination with a bioactiveglass.

Example 8

Dental Formulation

The dental formulations of Table 2 were prepared as follows: Glyceroland PEG 400 were added to the glass composition first, then theremaining ingredients of the formulation were separately added andthoroughly mixed with a spatula.

Example 9

Evaluation of Dental Formulation

The dental formulations of Table 2 were evaluated as follows: Humanmolars were lawfully obtained from bforbones (bforbones.com). Dentinediscs having a thickness of 1 mm were cut perpendicularly to the longaxis of the tooth above the cemento-enamel junction using a Buehlerlow-speed water cooled diamond saw. A smear layer was created on bothsides of the dentine discs by sanding 30 seconds using 500-grit sandingpaper. The smear was subsequently removed by treating with 6% citricacid for 3 mins, then rinsed with water, and dried at 37° C. The dentinediscs were randomly divided into control or experiment groups, eachcontaining at least 3 specimens, which received either a non-aqueoustoothpaste base formulation or a toothpaste containing 5% of 45S5; andthe toothpaste containing a disclosed glass composition, as listed inTables 1 and 2. The toothpaste and a powered tooth brush were used tobrush against both sides of the dentin discs for 1 min per side. Thespecimens were then rinsed with distilled water to remove visible tracesof toothpaste, and then stored in artificial saliva (1.5 mM CaCl₂), 0.9mM KH₂PO₄, 130 mM KCl, and 20 mM HEPES with pH 7.4). The procedure ofbrushing, rinsing, and storing each specimen in artificial saliva wasrepeated twice a day for 7 days, then the specimens were dried at 37° C.for 16 hrs and stored at RT before SEM.

The disclosure has been described with reference to various specificembodiments and techniques. However, many variations and modificationsare possible while remaining within the scope of the disclosure.

What is claimed is:
 1. A dental formulation comprising: a bioactiveglass composition in an effective amount comprising a source of: 2 to70% B2O3, 2 to 16% Al2O3, 5 to 30% CaO, 1 to 6% P2O5, 1 to 20% Na2O, and1 to 20% MgO, based on a 100 mol % total of the composition; and acarrier, in an effective amount based on the combined weight of thebioactive glass and the carrier.
 2. The dental formulation of claim 1,wherein: the bioactive glass further comprises a source of from 5 to 50%SiO₂, based on a 100 mol % total of the composition, and the carriercomprises a source of silica of from 1 to 25 wt % SiO₂ by super additionto the bioactive glass.
 3. The dental formulation of claim 1, whereinthe bioactive glass further comprises a source of from 1 to 20% K2O. 4.The dental formulation of claim 1, wherein the bioactive glass isessentially free of silica as a source of SiO₂, and free of inorganicpotassium salts as a source of K₂O.
 5. The dental formulation of claim1, further comprising a source of fluoride ion in an amount of from 1 to25 mol % by super addition to the composition.
 6. The dental formulationof claim 5, wherein the source of fluoride ion is selected from NaF,SnF2, CaF2, or a combination thereof.
 7. The dental formulation of claim1, wherein the bioactive glass is essentially free of a source offluoride ion.
 8. The dental formulation of claim 1, wherein thebioactive glass composition in an effective amount is from 0.1 to 10 wt%, and the suitable carrier in an effective amount is from 90 to 99.9 wt%.
 9. The dental formulation of claim 1, wherein the carrier comprisesat least one of an abrasive, a humectant, a flavorant, a colorant, anantibacterial agent, a surfactant, a whitening agent, a binder, or amixture thereof.
 10. The dental formulation of claim 1, wherein thesuitable carrier comprises one or more forms selected from: a gum, apaste, a powder, a toothpaste, a mouthwash, a poultice, a tea, a sucker,a spray, or a mixture thereof.
 11. The dental formulation of claim 1,wherein the bioactive glass composition in an effective amountcomprising a source of: 6 to 10% Al2O3, 15 to 25% CaO, 1.5 to 2% P2O5, 4to 8% Na2O, 6 to 10% K2O, and 6 to 10% MgO, based on a 100 mol % totalof the composition.
 12. The dental formulation of claim 1, wherein thebioactive glass composition comprises: 40 to 60% B2O3, and 0 to 10%SiO2, based on a 100 mol % total of the composition.
 13. The dentalformulation of claim 1, wherein the bioactive glass compositioncomprises: 20 to 40% B2O3, and 10 to 30% SiO2, based on a 100 mol %total of the composition.
 14. The dental formulation of claim 1, whereinthe bioactive glass composition comprises: 5 to 20% B2O3, and 30 to 50%SiO2, based on a 100 mol % total of the composition.
 15. A method oftreating dental hypersensitivity, comprising: reacting a borate orborosilicate glass composition with mammalian saliva to formhydroxycarbonated apatite or fluorapatite on a dentin surface, a dentintubule, or combination thereof.
 16. The method of claim 15, wherein theborate or borosilicate glass composition comprises: 2 to 70% B2O3, 2 to16% Al2O3, 5 to 30% CaO, 1 to 6% P2O5, 1 to 20% Na2O, and 1 to 20% MgO,based on a 100 mol % total of the composition.
 17. The method of claim16, wherein the borate or borosilicate glass composition in an effectiveamount comprising a source of: 6 to 10% Al2O3, 15 to 25% CaO, 1.5 to 2%P2O5, 4 to 8% Na2O, 6 to 10% K2O, and 6 to 10% MgO, based on a 100 mol %total of the composition.
 18. The method of claim 16, wherein the borateor borosilicate glass composition comprises: 40 to 60% B2O3, and 0 to10% SiO2, based on a 100 mol % total of the composition.
 19. The methodof claim 16, wherein the borate or borosilicate glass compositioncomprises: 20 to 40% B2O3, and 10 to 30% SiO2, based on a 100 mol %total of the composition.
 20. The method of claim 16, wherein the borateor borosilicate glass composition comprises: 5 to 20% B2O3, and 30 to50% SiO2, based on a 100 mol % total of the composition.
 21. The methodof claim 16, wherein the borate or borosilicate glass compositioncomprises: a source of fluoride ion in an amount of from 1 to 25 mol %by super addition to the composition.